Type 171 vessel MV Lisa shows some strength
Sometimes projects seem like everyday business at first sight – but, when we take a closer look, appearances can be deceiving. When SAL’s client Bedeschi approached the team with a shipment of four shiploaders for the OTEKO project in Taman, Russia, the complexity of this effort presented a one-of-a-kind engineering task.
“The engineering scope for this project was pretty clear and upfront: Safely load, transport, discharge and install the four partly dismantled shiploaders. One per shipment,” explained Florentin Edler, Project Engineer at SAL Engineering, and continued: “But to accommodate all parts of each shiploader on SAL’s Type 171 vessel MV Lisa, we had to make use of each and every centimetre of space available onboard. On top of that, the so-called ‘trailer front’ presented an interesting challenge.”
Due to the shape, size (53.2 × 15.8 × 29.7 metres) and weight (255 tonnes) of the “trailer front”, it was necessary to find a solution to safely hook-on the cargo, load it on board and disconnect the rigging afterwards without damaging the cargo. “We decided to make use of the ‘trailer front’s’ wheels to ensure smooth operations. We installed rails – 180 metres in total – on the weather deck of MV Lisa and a special on-board pulling configuration using the mooring lines to be able to easily move the ‘trailer front’ after loading. We literally sled it out of the rigging,” Florentin said.
The loading procedure was carried out in four steps:
Step 1: Prepare the rigging (consisting of a traverse, grommets, shackles and waterbags as counterweight).
Step 2: Move the cargo into the rigging by SPMTs.
Step 3: Swing the cargo aboard.
Step 4: Safely disconnect the rigging by pulling the cargo out using the on-board pulling configuration.
The vessel’s maximum lifting height was reached while loading the “trailer front”. The cargo and rigging were very close to the vessel’s structure, and the team had to make sure that the cargo was moved very precisely. Waterbags were not only used to keep the rigging levelled and to be able to hook-on, but also to level the cargo and ensure sufficient lifting stability.
It took about eight days, three tandem lifts (tripper, 460-ton gantry, gantry boom) and two single-hook lifts (trailer front, trailer rear) to safely load all cargo on board MV Lisa.
Two shiploaders have already arrived safely in Taman, and were installed successfully. The other two shipments will follow in 2021.